(ABC News) -- An explosion and fire in a Minneapolis building that contained apartments and a grocery store has left 14 people injured.
Officials are trying to determine whether everyone was able to get out of the building, which was quickly engulfed in flames.
The three-alarm fire began at 8:16 a.m., according to Minneapolis Fire Chief John Fruetel. The chief said there was an explosion followed by fire.
When crews arrived there were victims outside of the structure, Fruetel said, and there was heavy fire on second and third floors.
"Upon arrival, crews made entry into the first floor of this structure," Fruetel said. "Conditions became untenable very quickly, with major fires coming out of the second and third floors. Crews had to back out and go into defensive position outside of the building, applying water."
Some people were injured from jumping out of windows, authorities told ABC News. The cause of the blaze isn't yet known. More than 50 firefighters were on the scene.
A total of 14 people were taken to hospitals, and six were in critical condition, according to a statement from Minneapolis Assistant Chief of Administration Cherie A. Penn.
Ten victims, including three in critical condition, were taken to Hennepin County Medical Center, according to Penn, and three to the University of Minnesota. It was unknown where the other victim was transported.
There were nine or 10 apartments on the second and third floors, the chief said.
"Not everybody has been accounted for in this building," Fruetel said. "It is possible that some are still inside."
The temperature in Minneapolis was listed at -1 Fahrenheit.
Video from the scene showed flames shooting 20 feet from the building and victims outside in the frigid weather lying in the snow without coats or hats.
Abdi Warsame, a Minneapolis city councilman whose ward included the burned building, told reporters that there was a mosque behind the building that may have been damaged.
"The grocery store and apartments above have been damaged. And I think there is some damage to the mosque," Warsame said. "This whole area is very significant to the community."
The building was last inspected in 2012, according to Penn, and there were no outstanding inspection issues for the building.
The nearby Brian Coyle Center was opened for family and victims of the fire to reunite.